According to Fumia, when Sultan of Brunei was looking for a 'different' Ferrari, after he received 12 Testarossa spider, Pininfarina sent him the designs that were presented (and not choosen) for the Mythos. The one He choose was Fumia's proposal for the Mythos and He took 6 of them. That's why Ferrari never knew about it, those were designs used inside Pininfarina to develope the Mythos. When it was 'discovered' due to an internet scoop, Fumia, together with Roberto Bonetto went to Ferrari's PR Antonio Ghini to 'inform' them to keep good relationship between Ferrari and Pininfarina.
It's funny to report that Fumia was afraid that "if Sultan's of Brunei got involved in a car accident with a car full of Ferrari badges that was never 'officially' produced..."